contrib/bind-9.2.4rc7/lib/dns/include/dns/acl.h

   1 /*
   2  * Copyright (C) 2004  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 1999-2001  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: acl.h,v 1.20.2.1 2004/03/09 06:11:12 marka Exp $ */
  19
  20 #ifndef DNS_ACL_H
  21 #define DNS_ACL_H 1
  22
  23 /*****
  24  ***** Module Info
  25  *****/
  26
  27 /*
  28  * Address match list handling.
  29  */
  30
  31 /***
  32  *** Imports
  33  ***/
  34
  35 #include <isc/lang.h>
  36 #include <isc/magic.h>
  37 #include <isc/netaddr.h>
  38 #include <isc/refcount.h>
  39
  40 #include <dns/name.h>
  41 #include <dns/types.h>
  42
  43 /***
  44  *** Types
  45  ***/
  46
  47 typedef enum {
  48         dns_aclelementtype_ipprefix,
  49         dns_aclelementtype_keyname,
  50         dns_aclelementtype_nestedacl,
  51         dns_aclelementtype_localhost,
  52         dns_aclelementtype_localnets,
  53         dns_aclelementtype_any
  54 } dns_aclelemettype_t;
  55
  56 typedef struct dns_aclipprefix dns_aclipprefix_t;
  57
  58 struct dns_aclipprefix {
  59         isc_netaddr_t address; /* IP4/IP6 */
  60         unsigned int prefixlen;
  61 };
  62
  63 struct dns_aclelement {
  64         dns_aclelemettype_t type;
  65         isc_boolean_t negative;
  66         union {
  67                 dns_aclipprefix_t ip_prefix;
  68                 dns_name_t        keyname;
  69                 dns_acl_t         *nestedacl;
  70         } u;
  71 };
  72
  73 struct dns_acl {
  74         unsigned int            magic;
  75         isc_mem_t               *mctx;
  76         isc_refcount_t          refcount;
  77         dns_aclelement_t        *elements;
  78         unsigned int            alloc;          /* Elements allocated */
  79         unsigned int            length;         /* Elements initialized */
  80         char                    *name;          /* Temporary use only */
  81         ISC_LINK(dns_acl_t)     nextincache;    /* Ditto */
  82 };
  83
  84 struct dns_aclenv {
  85         dns_acl_t *localhost;
  86         dns_acl_t *localnets;
  87         isc_boolean_t match_mapped;
  88 };
  89
  90 #define DNS_ACL_MAGIC           ISC_MAGIC('D','a','c','l')
  91 #define DNS_ACL_VALID(a)        ISC_MAGIC_VALID(a, DNS_ACL_MAGIC)
  92
  93 /***
  94  *** Functions
  95  ***/
  96
  97 ISC_LANG_BEGINDECLS
  98
  99 isc_result_t
 100 dns_acl_create(isc_mem_t *mctx, int n, dns_acl_t **target);
 101 /*
 102  * Create a new ACL with room for 'n' elements.
 103  * The elements are uninitialized and the length is 0.
 104  */
 105
 106 isc_result_t
 107 dns_acl_appendelement(dns_acl_t *acl, dns_aclelement_t *elt);
 108 /*
 109  * Append an element to an existing ACL.
 110  */
 111
 112 isc_result_t
 113 dns_acl_any(isc_mem_t *mctx, dns_acl_t **target);
 114 /*
 115  * Create a new ACL that matches everything.
 116  */
 117
 118 isc_result_t
 119 dns_acl_none(isc_mem_t *mctx, dns_acl_t **target);
 120 /*
 121  * Create a new ACL that matches nothing.
 122  */
 123
 124 void
 125 dns_acl_attach(dns_acl_t *source, dns_acl_t **target);
 126
 127 void
 128 dns_acl_detach(dns_acl_t **aclp);
 129
 130 isc_boolean_t
 131 dns_aclelement_equal(dns_aclelement_t *ea, dns_aclelement_t *eb);
 132
 133 isc_boolean_t
 134 dns_acl_equal(dns_acl_t *a, dns_acl_t *b);
 135
 136 isc_boolean_t
 137 dns_acl_isinsecure(dns_acl_t *a);
 138 /*
 139  * Return ISC_TRUE iff the acl 'a' is considered insecure, that is,
 140  * if it contains IP addresses other than those of the local host.
 141  * This is intended for applications such as printing warning
 142  * messages for suspect ACLs; it is not intended for making access
 143  * control decisions.  We make no guarantee that an ACL for which
 144  * this function returns ISC_FALSE is safe.
 145  */
 146
 147 isc_result_t
 148 dns_aclenv_init(isc_mem_t *mctx, dns_aclenv_t *env);
 149
 150 void
 151 dns_aclenv_copy(dns_aclenv_t *t, dns_aclenv_t *s);
 152
 153 void
 154 dns_aclenv_destroy(dns_aclenv_t *env);
 155
 156 isc_result_t
 157 dns_acl_match(isc_netaddr_t *reqaddr,
 158               dns_name_t *reqsigner,
 159               dns_acl_t *acl,
 160               dns_aclenv_t *env,
 161               int *match,
 162               dns_aclelement_t **matchelt);
 163 /*
 164  * General, low-level ACL matching.  This is expected to
 165  * be useful even for weird stuff like the topology and sortlist statements.
 166  *
 167  * Match the address 'reqaddr', and optionally the key name 'reqsigner',
 168  * against 'acl'.  'reqsigner' may be NULL.
 169  *
 170  * If there is a positive match, '*match' will be set to a positive value
 171  * indicating the distance from the beginning of the list.
 172  *
 173  * If there is a negative match, '*match' will be set to a negative value
 174  * whose absolute value indicates the distance from the beginning of
 175  * the list.
 176  *
 177  * If there is a match (either positive or negative) and 'matchelt' is
 178  * non-NULL, *matchelt will be attached to the primitive
 179  * (non-indirect) address match list element that matched.
 180  *
 181  * If there is no match, *match will be set to zero.
 182  *
 183  * Returns:
 184  *      ISC_R_SUCCESS           Always succeeds.
 185  */
 186
 187 isc_boolean_t
 188 dns_aclelement_match(isc_netaddr_t *reqaddr,
 189                      dns_name_t *reqsigner,
 190                      dns_aclelement_t *e,
 191                      dns_aclenv_t *env,
 192                      dns_aclelement_t **matchelt);
 193 /*
 194  * Like dns_acl_match, but matches against the single ACL element 'e'
 195  * rather than a complete list and returns ISC_TRUE iff it matched.
 196  * To determine whether the match was prositive or negative, the
 197  * caller should examine e->negative.  Since the element 'e' may be
 198  * a reference to a named ACL or a nested ACL, the matching element
 199  * returned through 'matchelt' is not necessarily 'e' itself.
 200  */
 201
 202 ISC_LANG_ENDDECLS
 203
 204 #endif /* DNS_ACL_H */